KR20170038161A - Drying apparatus and drying method - Google Patents

Abstract

When an organic material film on a substrate is dried, the influence of moisture introduced into a treatment container is reduced to the maximum. A drying apparatus (100) includes a processing vessel (1) capable of evacuation, and a substrate supporter (3) serving as a substrate supporter for supporting a substrate (S) in the processing vessel (1). During a drying process, the drying apparatus (100) maintains the substrate (S) at a first height position when the pressure in the processing vessel (1) is in a range of the atmospheric pressure to 500 Pa and maintains the substrate (S) at a second height position lower than the first height position when the pressure in the processing vessel (1) is 3 Pa or less. The moisture in the processing vessel (1) may be rapidly discharged through an exhaust port (11a) of a bottom wall (11) by performing the reduced pressure exhaust while holding the substrate (S) at the first height position.

Description

[0001] DRYING APPARATUS AND DRYING METHOD [0002]

The present invention relates to a drying apparatus and a drying method which can be used for drying an organic material film on a substrate, for example, in the process of manufacturing an organic EL device.

An organic EL (Electro Luminescence) element is a light emitting element that uses luminescence of an organic compound generated by flowing an electric current. A laminate of a plurality of organic functional films (hereinafter, this laminate is referred to as an "EL layer" (Collectively referred to as " generic ").

Here, the EL layer may be formed, for example, from the anode side: [hole transporting layer / light emitting layer / electron transporting layer], [hole injecting layer / hole transporting layer / light emitting layer / electron transporting layer], or [hole injecting layer / hole transporting layer / light emitting layer / Layer], and the like.

The formation of the EL layer is performed by depositing or applying an organic material on the substrate for each layer. In the case of forming a fine pattern with high precision, it is assumed that it is advantageous to use an inkjet printing method as a coating method. A large amount of ink-derived solvent is contained in the organic material film printed on the substrate by the inkjet printing method. Vacuum drying is performed to remove the solvent. The dried organic material film is also baked in a low-oxygen atmosphere. By this baking treatment, the organic material film is changed to an organic functional film constituting the EL layer. Therefore, in the process of forming the EL layer using the ink-jet printing method, each step of printing, drying, and baking is repeatedly performed.

The vacuum drying apparatus used in the drying process is provided with an opening for carrying in and carrying out the substrate and a gate valve for closing the opening. Since the gate valve is opened at the time of loading and unloading of the substrate, the atmosphere is introduced into the processing container through the opening. In this state, when the interior of the processing vessel is depressurized for the drying treatment, the moisture in the air introduced at the time of opening the air coalesces with the lowering of the pressure to generate mist. If this mist is generated above the substrate, condensation may occur on the surface of the substrate, resulting in unevenness in the dry state, which causes problems such as display unevenness when used as a product such as an organic EL display.

With respect to the drying treatment of the organic functional ink applied on the substrate, in Patent Document 1, the pressure in the chamber is set to be equal to or lower than the vapor pressure of the solvent so that a uniform drying process can be performed in the surface of the substrate, There has been proposed to carry out a reduced-pressure drying process.

In Patent Document 2, in the step of drying the ink of the photosensitive resin composition under reduced pressure, the pressure is set to 5,000 to 50,000 Pa in the first stage, and once to the atmospheric pressure, the pressure is reduced to 500 Pa or less in the second stage, It has been proposed to improve the quality of the barrier ribs.

In Patent Document 3, proposal has been made to suppress the rupture of the coating film by changing the exhaust flow rate of the gas exhausted from the receiving chamber step by step in the vacuum drying process of the ink.

Patent Document 4 proposes a reduced-pressure drying apparatus having a plurality of nozzles capable of independently controlling the gas flow rate and gas type toward the organic material film applied on the substrate.

In the prior arts including the above Patent Documents 1 to 4, various designs have been made in the drying process of the organic material film applied on the substrate, but attention is paid to countermeasures against moisture mixed in the process container of the drying device It is not.

Japanese Patent Application Laid-Open No. 2010-272382 (claim 1, etc.) Japanese Patent Application Laid-Open No. 2008-116536 (paragraph 0032, etc.) Japanese Patent Application Laid-Open No. 2007-253043 (Claim 1, etc.) Japanese Patent Laid-Open Publication No. 2014-199808 (FIG. 1, etc.)

An object of the present invention is to provide a drying device and a drying method capable of minimizing the influence of moisture contained in a processing container when drying an organic material film on a substrate.

In order to solve the above problems, the drying apparatus of the present invention comprises:

A vacuum evacuable processing vessel having a bottom wall, a side wall and a top wall, removing the solvent in the organic material film applied to the surface of the substrate under a reduced pressure,

A substrate supporting portion for supporting the substrate in the processing chamber;

An exhaust device for decompressing and exhausting the interior of the processing vessel,

And a control unit for variably controlling a height position of the substrate supporting unit to support the substrate.

Further, in the drying apparatus of the present invention, in the process of decompressing and exhausting the inside of the processing container,

Maintaining the substrate at the first height position by the substrate support until at least the pressure in the processing vessel is lowered to the first pressure,

And controls the substrate to be maintained at a second height position lower than the first height position at least when the pressure in the processing container is equal to or lower than a second pressure lower than the first pressure.

The drying treatment method of the present invention is a drying treatment method comprising a treatment vessel capable of vacuum evacuation with a bottom wall, side walls and a top wall, a substrate support for supporting the substrate in the treatment vessel, and an exhausting device for evacuating the inside of the treatment vessel And a drying process for removing the solvent in the organic material film applied to the surface of the substrate by using an apparatus under reduced pressure and drying the solvent.

In the drying treatment method of the present invention,

Maintaining the substrate at a first height position by the substrate support until at least the pressure in the processing vessel is lowered to a first pressure,

And maintaining the substrate at a second height position lower than the first height position at least when the pressure in the processing vessel is equal to or lower than a second pressure lower than the first pressure.

In the drying apparatus and the drying method of the present invention, the first pressure may be 500 Pa or the second pressure may be 3 Pa.

In the drying apparatus and the drying method of the present invention, the sidewall is provided with an opening for carrying the substrate from an external transporting device,

The first height position may be a height position where the upper surface of the substrate is held above the upper end of the opening,

The second height position may be such that the upper surface of the substrate is at least 150 mm away from the lower surface of the wall.

The drying apparatus and the drying method of the present invention may be such that the organic material film is coated on the substrate by the ink jet printing method in the production of the organic EL device.

According to the present invention, it is possible to uniformly dry the organic material film within the substrate surface while minimizing the influence of moisture incorporated into the processing container. Therefore, by applying the present invention to a manufacturing process of, for example, an organic EL display or the like, the reliability of the product can be improved.

1 is a cross-sectional view showing a schematic structure of a drying apparatus according to an embodiment of the present invention.
Fig. 2 is an explanatory diagram of a plurality of support plates in the substrate support portion of the drying apparatus of Fig. 1;
Fig. 3 is an explanatory view of another state of the plurality of support plates in the substrate supporting portion of the drying apparatus of Fig. 1;
4 is a block diagram showing an example of the hardware configuration of the control unit.
5 is a process diagram for explaining the drying treatment method.
Fig. 6 is a process diagram for explaining the drying treatment method, following Fig. 5;
Fig. 7 is a process chart for explaining the drying treatment method, following Fig. 6;
8A is a schematic diagram for explaining the action of the substrate holding position in the present invention.
FIG. 8B is a schematic diagram for explaining the substrate holding position in the conventional technique. FIG.
FIG. 9A is another schematic diagram for explaining the function of the substrate holding position in the present invention. FIG.
Fig. 9B is a schematic diagram for explaining the substrate holding position in the comparative example. Fig.
10 is a graph showing the relationship between the pressure in the processing container and the amount of volatilization of the solvent.
11 is a flowchart showing an outline of a manufacturing process of an organic EL device.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. Fig. 1 is a cross-sectional view showing a schematic configuration of a single-feed type drying apparatus according to a first embodiment of the present invention. The drying apparatus 100 of the present embodiment is an apparatus for drying a glass substrate (hereinafter, simply referred to as "substrate") S for an organic EL display as an object to be processed, The solvent is removed and dried.

The drying apparatus 100 of the present embodiment includes a processing container 1 capable of vacuum evacuation and a substrate supporting section 3 serving as a substrate supporting section for supporting the substrate S in the processing container 1. [

<Processing vessel>

The processing container 1 is a pressure-resistant container which can be evacuated. The processing vessel 1 is formed of a metal material. As a material for forming the processing container 1, for example, aluminum, aluminum alloy, stainless steel or the like is used. The processing vessel 1 is provided with a bottom wall 11, four side walls 13 having a prism shape, and a top wall 15.

One side wall 13 is provided with a loading / unloading port 13a as an opening for loading / unloading the substrate S in the apparatus. The loading / unloading port 13a is for loading / unloading the substrate S from / to the outside of the processing vessel 1. A gate valve (GV) is provided at the loading / unloading port (13a). The gate valve GV has a function of opening and closing the loading and unloading port 13a and hermetically sealing the processing vessel 1 in a closed state and sealing the substrate 1 S).

The bottom wall 11 is provided with a plurality of exhaust ports 11a. The exhaust port 11a is connected to an external exhaust device 19 through an exhaust pipe 17. The exhaust port may be provided at the lower portion of the side wall 13. [

&Lt; Substrate support part &

A substrate supporting portion 3 for supporting the substrate S is disposed inside the processing vessel 1. [ As shown in Figs. 2 and 3, the substrate supporting portion 3 has a plurality of long supporting plates 4 arranged in a row. In Fig. 2, for example, nine support plates 4A to 4I are shown. A plurality of pins (not shown) are provided on the upper surface of the support plate 4, and the substrate S is supported by these pins.

The substrate supporting section 3 also has a lifting and lowering driving section 5 for lifting and lifting a part of the support plates 4 of the plurality of supporting plates 4. In the example shown in Figs. 2 and 3, the support plates 4A, 4C, 4E, 4G and 4I are movable support plates configured to be able to move upward and downward in synchronization with the elevation drive unit 5. [ The remaining support plates 4B, 4D, 4F and 4H are fixed to the bottom wall 11 without being lifted and lowered.

The lifting and lowering drive unit 5 has an actuator 5a, a shaft 5b driven up and down by the actuator 5a and a connecting portion 5c fixed to the tip of the shaft 5b. The actuator 5a is, for example, an air cylinder, a ball screw mechanism, or the like. The shaft 5b is inserted into a through-hole 11b provided in the bottom wall 11. In addition, the peripheries of the through-holes 11b are airtightly sealed. The connecting portions 5c are fixed to the bottom surfaces of the respective supporting plates 4A, 4C, 4E, 4G and 4I and fixed to the upper and lower support plates 4A, 4C, 4E, 4G, .

As shown in Fig. 2, the substrate supporting portion 3 is configured to mount the substrate S thereon in a state in which nine supporting plates 4A to 4I are arranged in a line. The substrate supporting portion 3 is also configured to mount the substrate S on movable supporting plates 4A, 4C, 4E, 4G and 4I. Then, with the support plates 4A, 4C, 4E, 4G, and 4I being lifted, the substrate S is transferred to and from an external transfer device (not shown). At this time, the fork-shaped substrate holding tool (not shown) of the external transfer apparatus is used for receiving the substrate S, for example, by using the gap between the support plates 4A and 4C and the gap between the support plates 4G and 4I Or delivery.

The substrate supporting portion 3 is not limited to the structure shown in Figs. 2 and 3, provided that it can displace the substrate S up and down. The number of the support plate 4 or the movable support plate in the substrate support portion 3 is arbitrary.

<Pressure control mechanism>

The drying apparatus 100 of the present embodiment further includes an exhaust device 19. By driving the exhaust device 19, the inside of the processing container 1 is configured to be evacuated to a predetermined degree of vacuum, for example, a pressure of about 0.1 Pa. The exhaust device 19 has, for example, a vacuum pump such as a turbo molecular pump or a dry pump. In the present embodiment, the dry pump and the turbo molecular pump can be switched according to the degree of vacuum in the processing vessel. Also, the exhaust device 19 may be an external device different from the drying device 100.

The drying apparatus 100 may further include an exhaust pipe 17 connecting the exhaust port 11a and the exhaust device 19 and an APC valve 23 disposed in the middle of the exhaust pipe 17. The internal space of the processing vessel 1 can be evacuated to a predetermined degree of vacuum by operating the vacuum pump of the exhaust device 19 and regulating the opening degree of the APC valve 23. [ The APC valve 23 is composed of one master valve and a plurality of slave valves, and each slave valve operates in conjunction with the master valve.

The drying apparatus 100 of the present embodiment further includes a pressure gauge 25 for monitoring the pressure in the processing vessel 1. [ The pressure gauge 25 transmits the measurement pressure in the processing vessel 1 as an electric signal to the APC valve 23 of the master valve.

In this embodiment, the exhaust device 19, the exhaust pipe 17, the APC valve 23, and the pressure gauge 25 constitute a pressure control mechanism for exhausting the inside of the processing container 1 under reduced pressure and regulating it to a predetermined pressure have.

<Gas supply mechanism>

The drying apparatus 100 of the present embodiment further includes a gas supply device 27 for supplying a gas into the processing container 1. [ A gas introducing portion 15a is provided in the wall 15 of the processing vessel 1. [ A gas supply unit 27 is connected to the gas introduction unit 15a. The gas introducing portion 15a may be provided at a position other than the top wall 15, for example, the side wall 13 or the like. The gas supply device 27 includes a gas supply source 29 for supplying gas to the gas introduction section 15a and one gas supply source 29 for connecting the gas supply source 29 and the gas introduction section 15a to supply the gas to the gas introduction section 15a Or a plurality of pipes 31 (only one is shown). The gas introducing portion 15a may be provided with a nozzle or a showerhead (not shown). The gas supply device 27 includes a mass flow controller (MFC) 33 for controlling the flow rate of the gas and a plurality of opening / closing valves 35 (only two are shown) in the middle of the pipe 31. The flow rate of the gas to be introduced into the processing vessel 1 from the gas inlet 15a is controlled by the mass flow controller 33 and the open / close valve 35. As the gas supplied from the gas supply source 29, for example, it is preferable to use an inert gas such as nitrogen gas or argon gas, or a substitution gas such as dry air. Further, the gas supply device 27 may be an external device different from the drying device 100.

<Control section>

The drying apparatus 100 of the present embodiment further includes a control unit 50. [ The respective components of the drying apparatus 100 are connected to the control unit 50 and controlled by the control unit 50, respectively. The control unit 50 is typically a computer. Fig. 4 shows an example of a hardware configuration of the control unit 50. Fig. The control unit 50 includes a main control unit 101, an input device 102 such as a keyboard and a mouse, an output device 103 such as a printer, a display device 104, a storage device 105, And a bus 107 connecting them to each other. The main control unit 101 has a CPU (Central Processing Unit) 111, a RAM (Random Access Memory) 112 and a ROM (Read Only Memory) The storage device 105 is not particularly limited as long as it can store information, for example, a hard disk device or an optical disk device. The storage device 105 is also adapted to record information on a computer readable recording medium 115 and to read information from the recording medium 115. [ The recording medium 115 is not limited to any type as long as it can store information, such as a hard disk, an optical disk, a flash memory, or the like. The recording medium 115 may be a recording medium on which a recipe of the drying method is recorded.

The control unit 50 executes the program stored in the ROM 113 or the storage device 105 by using the RAM 112 as a work area in the drying apparatus 100 of the present embodiment So that the substrate S can be processed. More specifically, the control unit 50 controls the drying unit 100 such that the temperature of the substrate S held by the respective components (e.g., The elevation drive section 5, the exhaust device 19, the gas supply device 27, etc.) of the substrate supporting section 3. For example, the control unit 50 can variably control the height position at which the substrate S is supported by the substrate supporting unit 3 during the drying process in the drying apparatus 100.

[Procedure of drying treatment]

Next, with reference to Figs. 5 to 7, the drying method of the embodiment of the present invention performed in the drying apparatus 100 configured as described above will be described.

As the previous step, an organic ink film is printed on the substrate S in a predetermined pattern with an external inkjet printing apparatus (not shown). The ink for forming the organic material film is composed of a solute and a solvent, and the component to be subjected to the drying treatment is mainly a solvent. Examples of the organic compound to be contained in the solvent include high boiling points. For example, 1,3-dimethyl-2-imidazolidinone (boiling point 220 ° C, melting point 8 ° C), 4 (4-tert-Butylanisole, boiling point: 222 캜, melting point: 18 캜), Trans-Anethole (boiling point: 235 캜, melting point: 20 캜), 1,2- 2-methoxybiphenyl, boiling point 274 ° C, melting point 28 ° C), phenyl ether (PhenylEther, boiling point 258.3 ° C, melting point 28 ° C), 2-ethoxy (2-Ethoxynaphthalene, boiling point 282 占 폚, melting point 35 占 폚), benzylphenyl ether (BenzylPhenylEther, boiling point 288 占 폚, melting point 39 占 폚), 2,6-dimethoxytoluene 2-propoxynaphthalene (boiling point: 305 ° C, melting point: 40 ° C), 1,2,3-trimethoxybenzene (boiling point: 235 ° C, melting point: 45 ° C) Cyclohexylbenzene (boiling point 237.5 DEG C, melting point 5 ), Dodecylbenzene (boiling point 288 ° C, melting point -7 ° C), 1,2,3,4-tetramethylbenzene (boiling point 203 ° C, melting point 76 ° C) . These high boiling point organic compounds may be blended in the ink in combination of two or more kinds.

5, the gate valve GV is opened, and the substrate S on which the organic material film is printed is transferred from the loading / unloading port 13a to the drying device (not shown) by the substrate holding tool 200 of the external transfer device, Into the processing vessel 1 of the substrate processing apparatus 100, and transfers it to the substrate supporting section 3. At this time, as described above, the actuators 5a of the lifting and lowering drive unit 5 are operated to lift the support plates 4A, 4C, 4E, 4G, and 4I and raise the substrate holding tool 200, And receives the substrate S.

After the substrate holder 200 is retracted, the gate valve GV of the drying apparatus 100 is closed and the substrate S (4) is held by the support plates 4A, 4C, 4E, 4G, ) At a predetermined height position (h ₁ ). Then, the exhaust device 19 is operated to start the depressurization and evacuation of the inside of the processing vessel 1, and the pressure in the processing vessel 1 is monitored by the pressure gauge 25 to control the opening degree of the APC valve 23 Decompressed to the degree of vacuum. In this way, a drying process for removing the solvent contained in the organic material film formed on the substrate S can be performed. In this case, with the operation of lifting the support plates 4A, 4C, 4E, 4G, 4I and receiving the substrate S from the substrate holder 200, the substrate S is raised to the height position h1 . Alternatively, after the substrate S is received from the substrate holding tool 200 and the substrate holding tool 200 is retracted (after the gate valve GV is closed as required), the support plates 4A, 4C, 4E , 4G, 4I) a may be further raised by adjusting the location of the substrate (S) to the height (h _1).

The upper surface of the substrate S is located above the height position h ₀ of the upper end of the loading / unloading port 13a (on the side of the top wall 15) in the stage from the start to the middle of the drying process, is held in a height position (h _1). That is, the height position h ₁ is higher than the height position h ₀ (h ₁ > h ₀ ). By starting the reduced pressure drying at the height position where h ₁ &gt; h ₀ , it is avoided that water in the air mixed in the processing vessel 1 due to opening of the gate valve GV flows upward of the substrate S can do. In this height position h ₁ , for example, when the longitudinal dimension of the substrate S is about 2.5 m x 2.2 m, the distance from the bottom surface of the top wall 15 to the top surface of the substrate S ) G is preferably 115 mm or more, more preferably 115 mm or more and 135 mm or less.

The maintenance of the height position h ₁ continues until at least the pressure in the processing vessel 1 drops to the first pressure. Here, the first pressure is, for example, 500 Pa.

Subsequently, the actuator 5a of the elevation drive section 5 is operated to lower the support plates 4A, 4C, 4E, 4G, and 4I while continuing the reduced pressure discharge in the processing vessel 1, The substrate S is lowered to the height position (h ₂ ). Then, at least the substrate S is held at the height position (h ₂ ) when the pressure in the processing container 1 is equal to or lower than the second pressure lower than the first pressure. The height position h ₂ is set such that the distance (gap) G from the bottom surface of the top wall 15 to the top surface of the substrate S is at least 150 mm or more, preferably 150 mm or more and 200 mm or less, Preferably not less than 155 mm and not more than 195 mm. In this manner, the substrate S is held at the second height position (h ₂ ) and subjected to reduced-pressure drying to promote volatilization of the solvent from the organic material film (ink) on the surface of the substrate S, Can be sufficiently diffused in the upper space of the substrate (S).

The maintenance of the height position h ₂ continues at least when the pressure in the processing container 1 is equal to or lower than the second pressure. Here, the second pressure is, for example, 3 Pa.

When the predetermined time has elapsed, the exhaust device 19 is stopped and the inside of the processing container 1 is raised to a predetermined pressure, and then the gate valve (GV) of the drying device 100 is opened. The substrate S lifted by the support plates 4A, 4C, 4E, 4G, and 4I is transferred to the substrate holding tool 200 of the external transfer apparatus and is taken out from the processing vessel 1. By the above procedure, the drying process for one substrate S is completed.

[Action]

Next, the operation of the present invention will be described with reference to Figs. 8A and 8B and Figs. 9A and 9B. As described above, since the gate valve GV is opened when the substrate S is carried in and out, air is introduced into the processing container 1 from the loading / unloading port 13a. When the inside of the processing vessel 1 is reduced in pressure for the drying treatment, the water W in the air introduced at the time of air opening due to the adiabatic expansion accompanies the lowering of the pressure, thereby generating mist.

Figure 8a shows a state in which to remain as in Fig 6, the substrate (S) to a height position (h ₁₎ discloses a pressure-drying treatment. Fig. Most, if you are holding the substrate (S) to the height (h _1), the water invading into the processing container 1 from the carry half the outlet (13a) (W) as shown in Figure 8a is a substrate (S) And it exists in the lower part. During or after the reception of the substrate S from the substrate holder 200, the substrate S is moved upward from the upper end of the loading / unloading port 13a, so that the volume of the space above the substrate S The moisture W entering the upper side of the substrate S from the loading / unloading port 13a at the time of opening the gate valve GV can also be introduced downward of the substrate S. For this reason, the exhaust port (11a) of the height (h ₁₎ the water bottom wall 11, the (W) in the by performing the reduced pressure exhaust in a state of holding the substrate (S), the processing container 1 shown in Figure 8a It can be discharged quickly. An exhaust port (11a) is more efficiently by the air stream downward to the air from the upper side toward containing, water (W) because it features a bottom wall (11) of the distance downward from the substrate (S) is maintained at a height position (h ₁₎ It can be exhausted.

On the other hand, in the prior art, after the substrate S is brought in and the gate valve GV is closed, the substrate S is immediately lowered and kept at the height position (h ₂ ), for example, . As a result, as shown in FIG. 8B schematically, by lowering the substrate S, the water W mixed into the processing vessel 1 flows into the upper side of the substrate S, And the fog was generated. When the fog is generated above the substrate S in this way, condensation occurs on the surface of the substrate S, and the uniformity of the dry state of the organic material film is impaired. As a result, when used as a product such as an organic EL display, Causing the problem of.

9A shows a state in which the substrate S is held at a height position (h ₂ ) to carry out a reduced-pressure drying process, similarly to FIG. 9A schematically shows the flow of the solvent gas (Gs) volatilized from the organic material film. When the pressure in the processing vessel 1 is close to the vapor pressure of the solvent, the amount of volatilization of the solvent from the organic material film sharply increases. The gap G which is the distance from the lower surface of the wall 15 to the upper surface of the substrate S is at least 150 mm or more at the height position h ₂ as described above. Therefore, a volume capable of sufficiently diffusing the high-concentration solvent gas Gs volatilized from the organic material film can be secured above the substrate S in the processing container 1. [ Height (h ₂₎ in, as shown in Fig. 9a, the organic material layer into the solvent gas (Gs) volatilize from being sufficiently diffused in the upper portion of the substrate (S), the side of the substrate (S) to form a gas stream And flows downward to be efficiently exhausted. As a result, the drying state of the organic material film can be made uniform within the plane of the substrate S, and the processing time until the completion of drying can be shortened. Even if the size of the substrate S is, for example, a size of about 2.5 m by 2.2 m in length and width, the gap G is maintained at 150 mm or more, so that the uniformity of the drying process in the plane can be achieved .

On the other hand, for example, when the drying process is continued at the height position h ₁ , as shown schematically in FIG. 9B, the volume of the space above the substrate S in the processing container 1 The high concentration solvent gas Gs volatilized from the organic material film stays above the substrate S and the drying efficiency is lowered. As a result, not only the treatment time until the end of drying is delayed but also condensation from the solvent gas (Gs) occurs on the surface of the substrate (S) It causes problems such as display unevenness.

As described above, in the drying apparatus 100 of the present embodiment, by changing the height position of the substrate S in accordance with the pressure in the processing vessel 1 during the drying processing, the amount of moisture mixed in the processing vessel 1 Uniform drying of the organic material film in the substrate (S) plane can be performed while minimizing the influence.

Then with reference to Fig. 10, and from the height (h ₁₎ described with respect to the timing of the transition to the height (h _2). 10, the vertical axis on the left side of the drawing shows the pressure when the inside of the processing vessel 1 is depressurized and evacuated, the vertical axis on the right side showing the amount of volatilization of the solvent from the organic material film, have. At the time from the start t0 to t1 of the decompressed exhaust, the pressure in the processing vessel 1 is lowered from atmospheric pressure to 500 Pa and further lowered to 3 Pa at t2. As described above, in the early stage of the drying treatment, it is necessary to efficiently remove the water mixed in the processing vessel 1. [ Therefore, it is preferable to maintain the height position h ₁ while the pressure in the processing container 1 is lowered from atmospheric pressure to 500 Pa (between t0 and t1). 10, represents a region (R1) for holding the height (h ₁₎ with a net shown.

On the other hand, the volatilization amount of the high boiling point solvent from the organic material film rapidly increases when the pressure in the processing container 1 is 3 Pa or less. Therefore, after the time t2 at which the pressure in the processing vessel 1 becomes 3 Pa or less, the volume of the space above the substrate S is sufficiently secured to promote the diffusion of the solvent, and the efficiency of the organic material film In order to achieve good uniform drying, it is desirable to maintain the height position (h ₂ ). 10, represents a region (R2) for holding the height (h ₂₎ to the net shown.

As described above, in order to achieve both the discharge of moisture from the inside of the processing vessel 1 and the uniform drying in the plane of the substrate S, the pressure in the processing vessel 1 is increased from t1 to t2 in between, it is effective to complete the transfer to the height (h ₂₎ from the height (h _1). Therefore, the switching from the height position h ₁ to the height position h ₂ is carried out within the range of the pressure in the processing vessel 1 of less than 500 Pa and more than 3 Pa, preferably in the range of 500 Pa or more and 8 Pa or more , And more preferably within a range of 100 Pa to 15 Pa or more. The descent from the height position h ₁ to the height position h ₂ may be performed continuously or stepwise. Further, in association with the lowering speed of the pressure inside the process vessel (1), for example, and even if t1 ~ t2 is gradually lowered to a height position (h ₂₎ from the height (h ₁₎ over time, once lowered to a more short time .

The time from the relationship between the pressure in the processing vessel 1 obtained in advance experimentally and the reduced pressure exhaust time in the transition from the elevation position h ₁ to the elevation position h ₂ is set to reach the predetermined degree of vacuum, The control unit 50 may control the time to send a control signal to switch the height position from the control unit 50 to the elevation driving unit 5. [ Alternatively, during the drying process, the pressure in the processing vessel 1 is monitored by the pressure gauge 25, and when the pressure measured by the pressure gauge 25 reaches a predetermined degree of vacuum, the control unit 50 causes the elevation drive unit 5 A control signal may be sent to switch the position.

As described above, in the drying apparatus 100 of the present embodiment, until at least the pressure in the processing vessel 1 is lowered to the first pressure, the substrate S is moved to the height position ( h ₁ ). On the other hand, under the second pressure, the substrate S is held at the height position (h ₂ ) in order to uniformly dry the organic material film in the plane of the substrate S. By changing the height position of the substrate S in accordance with the pressure in the processing vessel 1 during the drying process as described above, the influence of the moisture contained in the processing vessel 1 is minimized, Uniform drying of the material film can be performed. Therefore, for example, by using the drying apparatus 100 of the present embodiment in the manufacturing process of an organic EL display or the like, the reliability of the product can be improved.

[Application example to the manufacturing process of the organic EL device]

In the production of the organic EL device, a plurality of organic functional films are formed as an EL layer between the anode and the cathode. The drying apparatus 100 of the present embodiment can be applied to the production of any stacked-layer organic EL element. Here, the case where an organic EL device having a hole injection layer / a hole transporting layer / a light emitting layer / an electron transporting layer / an electron injection layer is manufactured from an anode side to an anode side as an EL layer is described as a specific process .

11 schematically shows a manufacturing process of the organic EL device. In this example, the organic EL device is manufactured by the steps of STEP1 to STEP8. In STEP 1, an anode (pixel electrode) is formed on the substrate S in a pattern determined by, for example, a vapor deposition method or the like. Next, in STEP 2, a bank (bank) made of an insulating material is formed between the positive electrodes by a photolithography method. As the insulating material for forming the barrier rib, for example, a polymer material such as a photosensitive polyimide resin can be used.

Subsequently, in STEP3, a hole injection layer is formed on the anode formed in STEP1. First, an organic material to be a material of the hole injection layer is printed on the anode partitioned by each partition by inkjet printing. Subsequently, the thus-printed organic material film is subjected to a reduced-pressure drying process for removing the solvent by using the drying apparatus 100. Subsequently, Subsequently, the substrate S after the drying treatment is transferred to a baking apparatus, and baking treatment is performed in the air to form a hole injecting layer.

Subsequently, in STEP4, a hole transport layer is formed on the hole injection layer formed in STEP3. First, an organic material to be a material of the hole transport layer is printed on the hole injection layer by the inkjet printing method. The organic material film printed in this manner is subjected to a reduced-pressure drying process for removing the solvent by using the drying apparatus 100. Subsequently, the substrate S after the drying treatment is transferred to a baking apparatus, and baking treatment is performed in the air to form a hole transporting layer.

Subsequently, in STEP5, a light emitting layer is formed on the hole transporting layer formed in STEP4. First, an organic material to be a material of the light emitting layer is printed on the hole transporting layer by the inkjet printing method. The organic material film printed in this manner is subjected to a reduced-pressure drying process for removing the solvent by using the drying apparatus 100. Subsequently, the substrate S after the drying treatment is transferred to a baking apparatus, and baking treatment is performed in the atmosphere to form a light-emitting layer. When the light emitting layer is composed of a plurality of layers, the above process is repeated.

Subsequently, an electron transport layer (STEP6), an electron injection layer (STEP7) and a cathode (STEP8) are sequentially formed on the light emitting layer by, for example, vapor deposition to obtain an organic EL element. Further, an electron transport layer (STEP6) and an electron injection layer (STEP7) can be formed by an inkjet printing method.

In the manufacturing process of such an organic EL device, the drying apparatus 100 is configured such that STEP3 (hole injection layer formation), STEP4 (hole transport layer formation), STEP5 (light emitting layer formation), STEP6 (electron transport layer formation) ). &Lt; / RTI &gt; That is, after the organic material film which is the previous stage of each layer is printed by the inkjet printing method, the organic material film can be subjected to the reduced pressure drying treatment using the drying apparatus 100. It is possible to change the height position of the substrate S in accordance with the pressure in the processing vessel 1 during the drying processing of the organic material film so that the influence of the moisture contained in the processing vessel 1 is minimized, Uniform drying of the material film can be performed. In addition, reliability of the drying process is enhanced, and reliability of products such as organic EL displays, for example, can be improved.

As described above, by using the drying apparatus 100, the drying process necessary for forming the EL layer in the manufacturing process of the organic EL device can be efficiently performed.

Although the embodiments of the present invention have been described in detail for the purpose of illustration, the present invention is not limited to the above embodiments, and various modifications are possible. For example, the manufacturing process of the organic EL device is not limited to that shown in Fig. For example, an organic EL layer having a structure in which an EL layer is layered in the order of [positive hole transporting layer / light emitting layer / electron transporting layer] or [hole injecting layer / hole transporting layer / light emitting layer / electron transporting layer] The drying apparatus 100 of the present invention can also be applied to the manufacture of devices.

1: Processing vessel
3:
11: bottom wall
13: Side wall
13a: Bringing-in exit
15:
15a: gas introduction part
17: Exhaust pipe
19: Exhaust system
23: APC valve
25: Manometer
27: Gas supply device
31: Piping
33: Mass flow controller (MFC)
35: opening / closing valve
50:
100: Drying device
S: substrate
GV: Gate valve

Claims (8)

A vacuum evacuable processing vessel having a bottom wall, a side wall and a top wall, removing the solvent in the organic material film applied to the surface of the substrate under a reduced pressure,
A substrate supporting portion for supporting the substrate in the processing chamber;
An exhaust device for decompressing and exhausting the interior of the processing vessel,
Wherein the substrate supporting part adjusts a height position of the substrate supporting part,
And,
In the process of evacuating the inside of the processing vessel,
Maintaining the substrate at the first height position by the substrate support until at least the pressure in the processing vessel is lowered to the first pressure,
And controls the substrate to be maintained at a second height position lower than the first height position at least when the pressure in the processing container is equal to or lower than a second pressure lower than the first pressure. The method according to claim 1,
Wherein the first pressure is 500 Pa and the second pressure is 3 Pa. 3. The method according to claim 1 or 2,
Wherein the side wall is provided with an opening for carrying the substrate from an external transporting device,
Wherein the first height position is a height position where the upper surface of the substrate is held above the upper end of the opening,
Wherein the second height position is such that the top surface of the substrate is at least 150 mm away from the bottom surface of the top wall. 3. The method according to claim 1 or 2,
Wherein the organic material film is applied on the substrate by ink jet printing in the production of the organic EL device. 1. A method for manufacturing a semiconductor device, comprising the steps of: applying a vacuum to a substrate having a bottom wall, a side wall and a top wall, a substrate support for supporting the substrate in the process container, and an exhaust device for evacuating the process container, And a drying treatment step of removing the solvent in the coated organic material film under a reduced pressure and drying it,
Wherein the drying process comprises:
Maintaining the substrate at a first height position by the substrate support until at least the pressure in the processing vessel is lowered to a first pressure,
Maintaining the substrate at a second height position lower than the first height position at least when the pressure in the processing vessel is equal to or lower than a second pressure lower than the first pressure
&Lt; / RTI &gt; 6. The method of claim 5,
Wherein the first pressure is 500 Pa and the second pressure is 3 Pa. The method according to claim 5 or 6,
Wherein the side wall is provided with an opening for carrying the substrate from an external transporting device,
Wherein the first height position is a height position where the upper surface of the substrate is held above the upper end of the opening,
Wherein the second height position is such that the top surface of the substrate is at least 150 mm away from the bottom surface of the top wall. The method according to claim 5 or 6,
Wherein the organic material film is applied on the substrate by inkjet printing in the production of the organic EL device.

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